Man, I've never had one kernel panic... ever.  And i've been using linux for over 2 years.  Maybe it's because I dont' go around typing "killall init" as root, or something.
I've had X freeze on me though (I blame the nvidia drivers that were out at the time)  It doesn't happen with the new drivers, fortunately.  I've never gotten Red Hat Linux 8 or 9 to crash.  And I leave my computer on all day, too.